Comment by JasperKazai

This is the effect of Blackrock Lager, one of the Brew of the Month brews. (June)You drink a random amount to get the Interal Combustion buff. When you have the buff on, you have some red smoke coming out of your mouth. When the 5 minutes passes, or you cancel the buff, you belch fire, similar to Dragonbreath Chili.